<?php

/*
 * This file is part of SwiftMailer. (c) 2004-2009 Chris Corbyn For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 */

/**
 * A null KeyCache that does not cache at all.
 * 
 * @package Swift
 * @subpackage KeyCache
 * @author Chris Corbyn
 */
class Swift_KeyCache_NullKeyCache implements Swift_KeyCache {
	/**
	 * Set a string into the cache under $itemKey for the namespace $nsKey.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @param string $string        	
	 * @param int $mode        	
	 * @see MODE_WRITE, MODE_APPEND
	 */
	public function setString($nsKey, $itemKey, $string, $mode) {
	}
	
	/**
	 * Set a ByteStream into the cache under $itemKey for the namespace $nsKey.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @param Swift_OutputByteStream $os        	
	 * @param int $mode        	
	 * @see MODE_WRITE, MODE_APPEND
	 */
	public function importFromByteStream($nsKey, $itemKey, Swift_OutputByteStream $os, $mode) {
	}
	
	/**
	 * Provides a ByteStream which when written to, writes data to $itemKey.
	 * NOTE: The stream will always write in append mode.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @return Swift_InputByteStream
	 */
	public function getInputByteStream($nsKey, $itemKey, Swift_InputByteStream $writeThrough = null) {
	}
	
	/**
	 * Get data back out of the cache as a string.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @return string
	 */
	public function getString($nsKey, $itemKey) {
	}
	
	/**
	 * Get data back out of the cache as a ByteStream.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @param Swift_InputByteStream $is
	 *        	to write the data to
	 */
	public function exportToByteStream($nsKey, $itemKey, Swift_InputByteStream $is) {
	}
	
	/**
	 * Check if the given $itemKey exists in the namespace $nsKey.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 * @return boolean
	 */
	public function hasKey($nsKey, $itemKey) {
		return false;
	}
	
	/**
	 * Clear data for $itemKey in the namespace $nsKey if it exists.
	 * 
	 * @param string $nsKey        	
	 * @param string $itemKey        	
	 */
	public function clearKey($nsKey, $itemKey) {
	}
	
	/**
	 * Clear all data in the namespace $nsKey if it exists.
	 * 
	 * @param string $nsKey        	
	 */
	public function clearAll($nsKey) {
	}
}
